Control of electric switches



"Jan. 10, 1933. R. wl-DEROE 1,394,139

CONTROL OF ELECTRIC SWITCHES Filed Aug. 8, 1930 MNr- /0 l2 A -/9 l8 F Inventor: RolPWider'cSe,

H is AttoTTI ey.

Patented Jan. 10, 1933 rarer fn'om wrnnnon orxanrsnonsr enmiia w, ass snon roenusnnrjiirincrnlo,

' COMPANY-LA oonnonarronhrnrrw YORK 1 CONTROL or nnnc'rnro swrrorrns Application filed August 8, 1930, SeriaLNo.

1 "i i :M'yi inyention relates to improvements in thepontroLofelectric switches, and more particularly} to improvements in the control, and

especially, the; remote control, of circuitil brealrers whtlsel opjening; is efiected in: re-

spouse ,;to; abnormal circuit;= conditions by loekoutirelayimeansr An object of my invention-this IQ provide iinprovedpmeans for con trollingithe circuitbreakers whereby to pre lti ventt-unnenes filry ollening of the circuit breakers, byzgreasonl of failure to reset, the

loekoutifrelay, before closing thecircuit breaker.-

Y v 'TEhe releasing: or, tripping contacts of pro- .l tecti-ve relays arein some cases; so constructed.

er-."'-Before rthe circuit breaker can be reclosed; howevery the-releasing or trippingv contacti'ofnthe. relay must be opened since otherwiselupon attempting to reclose-the circuit breaker it. will I immediately be released.

so Imam case ofir'emotely controlled switches,

the opening of the lockoutcontacts of the relaybefore :the-reclosing of the switches presents difl iculties. The resetting of the re-: lay-"contacts must be manualy effected.- For this' -p'urpose: an attendant must be sent to the point where-the relay is located'or the opening-of the relay contacts must be brought about throughth'e medium of a remote con trol-arrangement;

Since in remotely controlled plants it is necessary that as few control lines as possible be used, any arrangement for the resetting of the relay contacts which would make it possibleto getalong with as small a number of remote'controllines as is required'for'the remote operation of-the switch alone would be" advantageous.

According to my invention, this problem is solved ina simple manner by oontrollingthe resetting ofthe relay contacts simultaneously 473,952, and in Germany August-:16,-,1929.

with thereclosing of the switch; Inthistcajse the times of} the reclosing oi the; SW 'Ghl 011-] circuitbreaker and of the; resetting deaice are ;so adjusted. that therelaycontacts leave} the ,releasin g or tripping positioHbdDl'e-tha switch contacts reach the-closing; position.

This condition can be 1satisfiedgloypdifiierenti arrangements. For example ithe mass; of;- the magnet core or armature, in the closingz mechanism; of I the, circuitbreaker; can beflses E lected relatively to the mass-ofztheiarmatureifor the relay contacts so that the relaysgopl z their contacts ,in a shorter time, thaniitztakes to close; the; circuit breaken even in 1 the case of the simultaneous actuation:otibothimemy here. This time delay operation can, (it,

I course, be; eflected by the arrangementiofizag mechanical retardation device iIrthey-circuit breaken closing. mechanism. The'z timeainw terval can also be introducedielectrically by; providing the closing; magnet ,ofitheicircuit'f breaker, with a :shorti'circuitedi windinglworv ring. Withthis arrangement the-increase off the current in the Winding of; the relay which; does not have the short-circuited windingi takes place. more rapidly than in the closing coil of the circuit breaker-operating; mechaiinism. The two arrangements describedican 1 also be, combined; Al time elementzrelay-cam alsobeconnected in series with the;cir.cuit'; closing member of the circuit breaker-to. efiect the desiredtime lag. j-

1 Myqinvention will be better, understoodfrom the following description when COIlSid'n: eredin. connection with the accompanyingr -drawing,: and its scope will bepointedoutdn ed as a catch 7 vention is concerned. As illustrated, the relay 5'is of the lockout type and upon actuation of the contacts 6 is locked in the circuit closing position by suitable means illustrat- This catch is arranged to be released in any'suitable manner herein illustrated as a releasing coil 8.

The remote control of the circuit breaker 1 is effected through a control switch 9 which, when-closed on its contact 10, completes the circuit of the closing coil 3 of the circuit breaker to the control bus 11 and, when closed on its contact 12, completes the circuit of the tripping coil 4. In accordance witn my invention, I so arrange the control switch that, when it is moved to circuit closing position, it simultaneously energizes the circuit breaker closing means 3 and the resetting coil 8 of the lookout relay 5.

In order to introduce a time delay between the'release of the lookout relay 5 and the closing of the contacts of the circuit 1, I may apply to the circuit breaker operating mechanism a suitable mass 13 whereby to introduce a greater inertia effect than that of the movingparts of the relay 5. The circuit breaker reclosing movement may also be retarded by means of a short-circuited winding 1& which delays the building up of the flux in the closing coil magnet. Both of these retarding features may be used together if desired.

Assuming an abnormal condition on the circuit 2, such as to cause the operation of the protective relay 5, this relay will close its contacts 6 and they will be latched closed by the catch 7. Upon the closure of the contact 6 the circuit of the trip coil 4 will be comleted through the conductors 15, 16 and 17 hen it' is desired to reclose the circuit breaker, the switch 9 is moved to the left to close its contact 10. In so doing, the circuit of the closing coil is completed through the conductors 18, 19, 20 and 17. At the same time the circuit of the resetting or catch releasing magnet 8 is completed through the conductors 21, 22, control switch 9 and the conductors 20 and 17. The movable member of the protective relay 5 is, therefore, released and the contacts 6 opened. Due, however, to the time lag introduced in the circuit closing movement of the circuit breaker mechanism, the contacts 6 will be opened before the circuit breaker contacts are closed. Consequently the circuit breaker will be closed after the relay 5 has been reset so that there is no danger of an immediate reopening of the nee also breaker due to the failure of the relay contacts to be released.

It will be noted that this additional control or resetting of the protective relay means 5 is accomplished with the same number of control circuit conductors as 'is necessary for the opening and closing of the circuit breaker 1 so that the additional surety of releasing the lockout relay does not introduce any added expense in the way of extra conductors. This is an especially important item where the remote control is located for example in a distant station.

lVhile I have shown and described my invention in considerable detail, I do not desire to be limited tothe exact arrangements shown, but seek to cover in the appended claims allthose modificationsthat fall with in the true spirit and scope of my invention;

lVhat I claim as new and desire-to secure by Letters Patent of the United States is ing thereof including a lookout relay, control latch of said interrupter to efiect the openmeans for simultaneously resetting said lockout relay and efiecting the actuation of said operating means and means for effecting the movement of the contacts of the lockout relay from the releasingposition priorto the clos-i i ing of the contacts of the circuit interrupter. 2. In combination with an electric circuit, and a circuit breaker therefor, operating means including a closing coil foriefi'ecting the closing operation of said circuit breaker,

means for opening said circuitbreakerin response to abnormal circuit. conditions includmg a circuit closing lockout relay, control means for simultaneously releasing-the con-s tacts of said lockout relay from their: circuit closing position and effecting the energization of said closing coil, and means for delaying the closing of said-interrupter until the contacts of-said relay have moved from thei-rcircuit closing position.

3. In combination with an electric circuit and circuit interrupting means for controlling the circuit, operating means for closing said interrupting means, means for opening said circuit interrupting means in response to abnormal circuit conditions-including a lockout relay, means for latching said relay in a position to effect the opening of said circuitinterrupting means and control means. for

simultaneously releasing said latchingmeans and effecting the energlzatlon of said operating means. c 4:. In combination with an electric circuit and a circuit breaker therefor, operating means for closing said circuit breaker, means,, for opening said circuit breaker in response,

to abnormal circuit conditions including a circuit closing lockout relay, control means 4 for simultaneously releasing the contacts of said lockout relay from the circuit closing position and efiecting the actuation of said operating means, and means for introducing a time delay between the opening of the contacts of the lockout relay and the closing of the contacts of the circuit interrupter.

5. In combination with a circuit breaker, means for closing said circuit breaker means for opening said circuit breaker including a circuit closing lockout relay, control means for releasing the contacts of said lockout relay from their circuit closing position and efiecting the actuation of said closing means and means for delaying the closing of the contacts of the circuit interrupter until after the opening of the contacts of the lookout relay. In witness whereof, I have hereunto set my hand this 15th day of July 1930.

ROLF WIDEROE. 

